Cutaneous Mucormycosis by Saksenaea vasiformis: An Unusual Case Report and Review of Literature

Epidemiology of Mucormycosis in Greece; Results from a Nationwide Prospective Survey and Published Case Reports

Mucormycosis has emerged as a group of severe infections mainly in immunocompromised patients. We analysed the epidemiology of mucormycosis in Greece in a multicentre, nationwide prospective survey of patients of all ages, during 2005-2022. A total of 108 cases were recorded. The annual incidence declined after 2009 and appeared stable thereafter, at 0.54 cases/million population. The most common forms were rhinocerebral (51.8%), cutaneous (32.4%), and pulmonary (11.1%). Main underlying conditions were haematologic malignancy/neutropenia (29.9%), haematopoietic stem cell transplantation (4.7%), diabetes mellitus (DM) (15.9%), other immunodeficiencies (23.4%), while 22.4% of cases involved immunocompetent individuals with cutaneous/soft-tissue infections after motor vehicle accident, surgical/iatrogenic trauma, burns, and injuries associated with natural disasters. Additionally, DM or steroid-induced DM was reported as a comorbidity in 21.5% of cases with various main conditions. Rhizopus (mostly R. arrhizus) predominated (67.1%), followed by Lichtheimia (8.5%) and Mucor (6.1%). Antifungal treatment consisted mainly of liposomal amphotericin B (86.3%), median dose 7 mg/kg/day, range 3-10 mg/kg/day, with or without posaconazole. Crude mortality was 62.8% during 2005-2008 but decreased significantly after 2009, at 34.9% (p = 0.02), with four times fewer haematological cases, fewer iatrogenic infections, and fewer cases with advanced rhinocerebral form. The increased DM prevalence should alert clinicians for timely diagnosis of mucormycosis in this patient population.

Cutaneous Invasive Fungal Infections with Saksenaea Species in Immunocompetent Patients in Europe: A Systematic Review and Case Report

Invasive fungal infections from Saksenaea, a fungus belonging to the Mucorales, have been rarely reported in central European climate zones. This study aims to raise awareness of invasive cutaneous infections with Saksenaea species. The first case of a cutaneous infection was diagnosed in Switzerland in an immunocompetent 79-year-old patient. A minor skin trauma of her left lower leg led to a fulminant infection causing necrosis and extensive loss of tissue. The combination of surgical debridement and administration of antifungal agents averted a prolonged course with a possible worse outcome. A pedicled hemisoleus muscle flap was used to reconstruct the defect and treatment was continued for 63 days.

Methods

A systematic review in accordance with the Preferred Reporting Items for Systematic review and Meta-Analysis guidelines was conducted to identify all European cases of infection with Saksenaea species in immunocompetent hosts. The epidemiology, clinical presentation, microbiological diagnosis, and management of cases reported in Europe were summarized and analyzed.

Conclusions

The prognosis of soft tissue infections with Saksenaea species. depends on early diagnosis and appropriate antifungal and surgical treatment. Reconstruction can be successful under ongoing antifungal treatment.

High-Temperature-Tolerant Fungus and Oomycetes in Korea, Including Saksenaea longicolla sp. nov

Global temperatures are steadily increasing, leading to significant changes in microbial diversity and ecology. In the present study, we isolated high-temperature-growing fungi and fungi-like group (Oomycota) strains from freshwater environments of Korea and identified them based on cultural, morphological, and multilocus phylogenetic analyses. As a result, we introduce Saksenaea (Fungi) isolates as a new species, Saksenaea longicolla sp. nov. and record Phytophthora chlamydospora and P. lagoariana (Oomycota) new to Korea. In the growth experiments, they exhibited high-temperature tolerance, which can grow at 35-40 °C but become inactive at 4 °C and below. This study confirms the presence of high-temperature-tolerant fungi and oomycetes in Korea and suggests that the Korean climate conditions are changing in favor of these species. This indicates that climate warming is altering microbial distributions in freshwater environments.

Mucormycosis with cutaneous involvement. A retrospective study of 115 cases at a tertiary care hospital in Mexico

BACKGROUND/OBJECTIVES

Cutaneous mucormycosis is an emerging opportunistic mycosis caused by Mucorales. It can be divided into primary caused by trauma and secondary by extension of rhino-cerebral and disseminated cases. The objective is to present a retrospective study of cases of mucormycosis with cutaneous involvement.

METHODS

A retrospective and descriptive study was carried out. Mucormycosis patients were included and divided into two groups: a) Primary Cutaneous and b) Secondary Cutaneous. Mycological tests were performed; the agents were identified by morphology and molecular studies (PCR and sequencing); some cases underwent histopathology. Clinical data and response to treatment were collected.

RESULTS

115 cases were included, 18 of primary, and 97 of secondary cutaneous mucormycosis. Primary cutaneous mucormycosis was most associated with adhesive bands (44.4%) and trauma from traffic accidents (33.3%). The principal clinical form was extensive and deep necrotic ulcers. Secondary cutaneous mucormycosis cases were rhino-cerebral with uncontrolled diabetes (81.4%) The most frequent clinical presentation was necrosis of the eyelid and the nose (65.9%). In both groups, the principal agent was Rhizopus arrhizus, 38.8% and 74.2% respectively. The most effective treatment was the combination of amphotericin B with surgical debridement. The clinical and mycological cure was achieved in 31.0% of primary cases, and 44.4% for secondary cases.

CONCLUSION

Primary cutaneous mucormycosis is caused by implantation of the Mucorales due to trauma or rupture of the cutaneous barrier-breach, and secondary cutaneous mucormycosis develops as part of the rhino-cerebral process. The response to treatment depends on the extension and depth, as well as the predisposing factors.

Combat trauma-related invasive fungal wound infections

Purpose of review

This review highlights research from the past five years on combat trauma-related invasive fungal wound infections (IFIs) with a focus on risk stratification to aid patient management, microbiology, and diagnostics.

Recent Findings

A revised classification scheme stratifies wounds into three risk groups: IFI, High Suspicion of IFI, and Low Suspicion of IFI. This stratification is based on persistence of wound necrosis and laboratory fungal evidence, presence of signs/symptoms of deep soft-tissue infections, and the need for antifungals. Use of this classification could allow for prioritization of antifungal therapy. Further, IFIs delay wound healing, particularly when caused by fungi of the order Mucorales. Lastly, molecular sequencing offers promising and complimentary results to the gold standard histopathology.

Summary

Optimal management of combat-related IFIs depends on early tissue-based diagnosis with aggressive surgical debridement and concomitant dual antifungal therapy. Further research on clinical decision support tools and rapid diagnostics are needed.

Disseminated Mucormycosis Due to Saksenaea vasiformis Complex in an Immunocompetent Adult with Sustained Response to Posaconazole Treatment

Saksenaea vasiformis complex is an emerging cause of mucormycosis. We report a case of an immunocompetent patient presenting with a non-resolving lung mass who developed multiple skin nodules. Skin biopsy yielded Saksenaea vasiformis complex. This showcases an uncommon occurrence of disseminated Saksenaea infection without cutaneous inoculation that improved with posaconazole.

Unusual case of otomycosis caused by Saksenaea vasiformis

Saksenaea vasiformis is a species of the order Mucorales rarely reported as a cause of human mucormycosis. We report an unusual case of S. vasiformis otitis occurring in a diabetic woman after penetration of an insect in the right ear. Direct microscopic examination of the clinical sample showed hyaline and non septate hyphae belonging to the order Mucorales. Fungal identification was performed by sequencing the ITS region of the rDNA. To our knowledge, this is the first report of S. vasiformis infection in Tunisia.

Rare indolent zygomycosis caused by subcutaneous Saksenaea vasiformis infection

We report an immunocompetent male child with chronic, indolent subcutaneous limb infection akin to basidiobolomycosis, but was shown by PCR method to be caused by a mucoralean fungus Saksenaea vasiformis. Treatment with oral potassium iodide solution was effective. This finding highlights the consideration of treatment decision according to the phenotypic severity as opposed to species identified.

Saksenaea dorisiae sp. nov., a New Opportunistic Pathogenic Fungus from Europe

A new species, Saksenaea dorisiae (Mucoromycotina, Mucorales), isolated from a water sample originating from a private well in Manastirica, Petrovac, in the Republic of Serbia (Europe), is described and illustrated. The new taxon is well supported by multilocus phylogenetic analysis that included the internal transcribed spacer (ITS) region, domains D1 and D2 of the 28S rRNA gene (LSU), and translation elongation factor-1α gene (tef-1α), and it is resolved in a clade with S. oblongispora and S. trapezispora. This fungus is characterized by its moderately slow growth at 15 and 37°C, sparse rhizoids, conical-shaped sporangia, and short-cylindrical sporangiospores. Saksenaea dorisiae is a member of the opportunistic pathogenic genus often involved in severe human and animal mucormycoses encountered in tropical and subtropical regions. Despite its sensitivity to several conventional antifungals (terbinafine and ciclopirox), the fungus can potentially evoke clinically challenging infections. This is the first novel taxon of the genus Saksenaea described from the moderately continental climate area of Europe.